AbstractHuman population growth and development have degraded freshwater ecosystems through direct negative effects on basal resources and higher trophic levels. Knowledge of how basal resources are influenced by anthropogenic activities is needed to examine foodweb responses and to evaluate negative effects of human disturbance. We combined quantitative sampling of all putative resources and consumers and naturally occurring stable isotopes of resource C and N to investigate how land use influences characteristics of basal resources (leaf litter, fine particulate organic matter [FPOM] suspended in water, FPOM deposited in pools, and epilithon) and the invertebrate communities in 9 streams of British Columbia (Canada) on a seasonal basis. Study streams were grouped as forest, cropland, and urban, based on percentages of land use in their catchments. We tested for seasonal and spatial differences in biomass, isotopic variability, and overlap of different basal resources and their relationships with inverte...